Dental paralleling apparatus



Oct. 13,

Filed Nov.

M. COWAN ETAL DENTAL PARALLEL-INC APPARATUS 2 Sheets-Sheet 1 FIG. 2b.

INVENTORS uonms cow ROBERT 'SPALTEN ATTO EY Oct. 13, 1964 M. COWAN El'AL 3,152,401

DENTAL PARALLELING APPARATUS Filed Nov. 15, 1962 2 Sheets-Sheet 2 INVENTORS MORRIS COWAN ROBERT SPALTEN ORNEY United States Patent Ofilice 3,152,401 Fatented Get. 13, 1964 3,152,401 DENTAL PARALLELING APPARATUS lviorris Cowan, 32% Central Parlr Elk, and Rohert Spalten, 333 Central Park W., both of New York, N.Y. Filed Nov. 15, 1962, Ser. No. 237,833 7 Claims. ((31. 32-67) This invention relates to dental fixtures and in particular to paralleling devices for preparing parallel holes in and parallel surfaces on the teeth, or models of the teeth.

In constructing fixed bridge work, as Well as in many other dental operations, it is often necessary to drill parallel holes in the teeth or to grind precisely parallel surfaces thereon. These operations may be performed without mechanical aids but the dentist must possess considerable skill and dexterity to achieve the required degree of precision. As a result, various mechanical devices have been developed to assist him in accomplishing this task. However, none of the fixtures or guides thus far available has proved entirely satisfactory for both of these purposes.

Accordingly, it is an object of our invention to provide an improved paralleling device for guiding the dental hand piece during drilling and grinding operations.

Another object is to provide a paralleling device for precisely drilling parallel holes in the teeth.

Still another object is to provide a paralleling device which may be made to conform to the mouth of the patient and which can be accurately replaced in the same position in the mouth as often as necessary.

Yet another object is to provide a paralleling device which may be used for drilling parallel holes in the incisal and occlusal surfaces of the teeth and which may be adapted for drilling holes in the axial suriaces of the teeth.

A further object is to provide a paralleling device which is continuously adjustable over a given angular range and is not limited to a finite number of settings.

A still further object is to provide a paralleling device which may be used in the laboratory for preparing parallel holes and surfaces in models of the teeth.

in the present invention, a paralleling device is provided which comprises a positioning member held firmly between the occlusal surfaces of the upper and lower teeth on one side of the mouth, a handpiece holder, and a hillage coupling the positioning member to the handpiece holder.

In one embodiment of our invention, the positioning member includes spaced upper and lower bite-on plates havin thermoplastic layers aflixed to their outer surfaces and a rotatable swivel block secured between their inner surfaces. The axis of rotation of the swivel block defines a vertical reference direction which is substantially parallel to the axial surfaces of the teeth when the positioning member is placed in the mouth. The linkage comprises a universal joint coupled to the swivel block, an extension member rotatably connected to the universal joint, and a slide member coupled to the extension member. The handpiece holder is secured to the slide member.

The direction of the longitudinal axis of the drill or grinding tool required to perform a given operation is defined as the operating direction. The tool axis is adjusted to this direcion by rotating the universal joint to the desired position and then looking the joint in place. The universal joint and the slide member are coupled to the extension member by pins which permit the handpiece holder to be moved in the operating direction and in a plane perpendicular thereto. Thus, with the positioning member gripped between the teeth on one side of the mouth the dentist can drill precisely parallel holes in the incisal and occlusal surfaces of all of the teeth not coveved by the ite-on plates. Further, the axial surfaces of these teeth may be made parallel by grinding. The handpiece may be rotated in the holder to permit the dentist to work on both the upper and lower teeth.

in another embodiment of our invention useful for drilling holes in the axial surfaces of the teeth, the positioning member is fastened to a horizontal adaptor member hold rigidly between the upper and lower jaws. The axis of rotation of the swivel block which forms a part of the positioning member defines a horizontal reference direction which is generally parallel to the median line of the face, i.e. a line drawn perpendicularly through the center of the face and mouth and passing between the central incisors of both the upper and lower jaws. With this arrangement, the drill can be locked at the desired angle (the operating direction) relative to the horizontal reference direction by adjustment of the universal joint. it can then be translated freely in the operating direction and also positioned in a plane perpendicular to the operating direction.

The above objects of and the brief introduction to the present invention will be more fully understood and further objects and advantages will become apparent from a study of the following description in connection with the drawings, wherein:

FIG. 1 is a perspective View of one embodiment of our invention;

FIGS. 2:: and 2b are side and top views respectively of the bite-on plates;

FIG. 3 illustrates details of the universal joint;

FEGS. 4a and 4b are cut-away side and top views of our paralleling device; and

FIG. 5 is another embodiment of our invention used for drilling parallel holes in the axial surfaces of the teeth.

Referring to FIG. 1, the paralleling device is shown being used for drilling a hole in the occlusal surface 10 of a molar on the left side of the mouth. A positioning member including wedge-shaped bite-on plates 11 and 12 is held firmly between the occlusal surfaces of the upper and lower bicuspids and molars on the right side of the mouth. The width of plates 11 and 12 is slightly greater than the width of the teeth to permit the plates to be held securely without filling excessive space in the mouth. (For clarity, only the lower jaw is shown in FIG. 1 but it shall be understood that the upper teeth on the right side of the mouth press against the upper bite-on plate 12.)

Thermoplastic layers 13 are afiixed to the outer surfaces of bite-on plates 11 and 12. As shown in FIGS. 2a and 2b, the outer surfaces of the bite-on plates are provided with ridges 14 to improve the adherence of the thermoplastic material. This material becomes soft when heated to a moderate temperature but hardens in a relatively short time at body temperaure. In use, thermoplastic layers 13 are first softened by heating, the patient then biting into the plastic to form impressions in layers 13 of the occlusal surfaces of the upper and lower teeth. This establishes the location of the positioning member in the mouth so that it can be removed and subsequently replaced without changing the position of the fixture.

A swivel block 15 is rotatably secured between the bite-on plates 11 and 12 by a bite-on pin 16 wlu'ch passes through a hole in the block. The axis of rotation of block 15 defines a vertical reference direction which is essentially parallel to the axial surfaces of the teeth as indicated by the dashed line 18 of FIG. 1.

A universal joint 19 is coupled to swivel block 15 by a ball member 29 which is pressed into an opening in the block. As shown in detail in FIG. 3, the ball member 28 has an essentially spherical portion 21 held against the concave end of an externally threaded wrist bearing 22 by an internally threaded lock nut 23. Wrist bearing a 22 is secured tightly in place by a nylon insert 24 which presses radially outward against lock nut 23. The position of bearing 22 is adjusted so that it applies sufficient pressure against the spherical portion of ball member 21 to prevent free or loose motion of bearing 22 relative to ball member 21 when lock screws 17 are open, yet permits the wrist bearing to be rotated about the sphere 21 by application of a moderate force. When the wrist hearing has been adjusted to the desired position, it is held rigidly in place by tightening screws 17 onto the serrated surface 25 of sphere 21.

Wrist bearing 22 is rotatably fastened to one end of an extension member 26 by a wrist pin 27. The other end of extension member 26 is rotatably secured to a slide member 28 by a slide pin 29. A handpiece holder comprising a pin block 39 and a swivel plate 31 is secured to the slide member 28 by a pair of support arms 32 and 33, swivel plate 31 being mounted between the lower support arm 33 (FIG. 4a) and an adjustable swivel plate pin 34 threaded into pin block 3%. The lower support arm 33 and pin 34 support the handpiece 35.

FIGS. 4a and 4b are side and plan views respectively showing the paralleling device in partial cross-section. The wrist bearing 22 of universal joint 19 has been rotated so that the operating direction indicated by dashed lines 36 through the drill 37 (FIG. 1) and pins 34, 2?, and 27 makes a predetermined angle with the vertical reference direction 18. Thus, with the bite-on plates 11 and 12 fixed in position between the teeth of the patient as previously described, a hole may be drilled at the desired angle in the occlusal or incisal surface of any tooth not covered by the bite-on plates. A second hole parallel to the first one may then be accurately bored by rotating the drill about the axes through pins 34, 29, 2'7 and 16 to the desired position. It shall be noted that rotation about these pins maintains the drill at a fixed angle relative to the vertical reference direction 18 and therefore to the surfaces of the teeth. The drill is positioned in the operating direction by translating slide member 28 along slide pin 29. Holes may be drilled in the upper teeth by rotating the position of handpiece in swivel plate 31 through 180.

FIG. 5 shows another embodiment of our invention being used for drilling a hole in the labio-lingual direction in a lower left bicuspid. In this modification, a horizontal adaptor member 40 is rigidly held between the jaws on the right side of the mouth. The positioning member is attached to the adaptor member 4% with the axis of rotation 41 of swivel block 15 generally parallel to the median line of the face. joint 19 so that the longitudinal axis of the drill 37 is parallel to the desired operating direction 42, parallel holes may be drilled in the labio-lingual or buccai-lingual directions in a manner similar to that described for drilling holes in the axial direction of the teeth.

Although the description has been primarily directed toward the drilling of parallel holes, it should be understood that the paralleling device may also be used for grinding parallel surfaces on the teeth by substitution of a grinding tool. paring models of teeth in the laboratories by supporting it in a suitable jig. If desired, the bite-on plates 11 and 12 and adaptor member 40 may be omitted, the universal joint 19 being supported by a laboratory fixture designed for this purpose. 7

As many changes could be made in the above construction and many different embodiments could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. A paralleling device comprising (a) upper and lower spaced wedge-shaped bite-on plates having inner and outer surfaces,

By positioning the universal Our device may also be used for pre-,

(b) first and second thermoplastic layers secured to the outer surfaces of said upper and lower bite-on plates,

(0) a swivel block rotatably secured to the inner surfaces of said upper and lower bite-on plates, the axis of rotation of said swivel means defining a vertical reference direction,

(d) a universal joint, said universal joint comprising a ball member coupled to said swivel block and a wrist bearing slidably engaging said ball member,

(e) an extension member rotatably coupled to said wrist bearing, the axis of rotation of said extension member being determined by the relative positions of the wrist bearing and ball member of said universal joint and defining an operating direction, said operating direction being at a predetermined angle with respect to said vertical reference direction,

(1) a slide member coupled to said extension member,

said slide member being translatable in said opera"- ing direction and rotatable in a plane perpendicular thereto, and

(g) a holder coupled to said slide member, said holder being adapted for holding a dental tool.

. 2. A paralleling device comprising (a) positioning means including upper and lower spaced wedge-shaped bite-on plates and swivel means rotatably secured between said upper and lower biteon plates, the axis of rotation of said swivel means defining a reference direction,

(b) a universal joint, said universal joint comprising a ball member coupled to said swivel means and having a spherical portion, an externally threaded wrist bearing, and an internally threaded loci: nut threadably engaging said wrist bearing, said lock nut maintaining said wrist bearing in slidable engagement with the spherical portion of said ball member,

(0) holding means for supporting a dental tool, and

(d) means for coupling said holding means to said universal joint, said means permitting translation of said tool holding means in an operating direction determined by the relative positions of the wrist bearing and ball member of said universal joint and permitting movement of said tool holder in a plane perpendicular to said operating direction, said operating direction being at a predetermined angle with respect to said vertical reference direction.

3. A paralleling device comprising (a) upper and lower wedge-shaped bite-on plates each having an inner surface and a ridged outer surface,

(b) first and second thermoplastic layers secured to the outer surfaces of said upper and lower bite-on plates,

(0) a swivel block rotatably secured to the inner surface of said upper and lower bite-on plates, the axis of rotation of said swivel means defining a vertical reference direction,

(d) a universal joint, said universal joint comprising a ball member coupled to said swivel means and having a serrated spherical portion, an externally threaded wrist bearing, an internally threaded lock nut threadably engaging said wrist bearing, said lock nut maintaining said wrist bearing in slidable engagement with the spherical portion of said ball member, and an insert radially positioned in said wrist bearing, said insert pressing outward against said lock nut to prevent relative movement of said lock nut and said wrist bearing,

(e) an extension member rotatably coupled to said wrist bearing, the axis of rotation of said extension member being determined by the relative positions of the wrist bearing and ball member of said universal joint and defining an operating direction, said opera ing direction being at a predetermined angle with respect to said vertical reference direction,

(f) a slide member coupled to said extension member,

said slide member being translatable in said operating direction and rotatable in a plane perpendicular thereto, and

(g) a holder coupled to said slide member, said holder being adapted for holding a dental tool.

4. A paralleling device comprising (a) a wedge-shaped adaptor member,

(b) first and second thermoplastic layers secured to the upper and lower surfaces of said wedge-shaped adaptor member,

(0) swivel means rotatably secured to the end of said adaptor member, the axis of rotation of said swivel means defining a horizontal reference direction,

(:1) universal means including first and second members, said first member being attached to said swivel means and said second member being angularly adjustable with respect to said first member to establish a predetermined operating direction, said operating direction being at a predetermined angle with respect to said horizontal reference direction,

(e) extension means rotatably coupled to the second member of said universal means, said extension means being rotatable in a plane perpendicular to said operating direction,

(1) holding means for supporting a dental tool, and

(g) means coupled to said extension means and to said holding means for translating said holding means in said operating direction.

5. A paralleling device comprising (a) a wedge-shaped adaptor member,

(b) swivel means rotatably secured to the end of said adaptor member, the axis of rotation of said swivel means defining a horizontal reference direction,

(c) universal means including first and second members, said first member being attached to said swivel means and said second member being angularly adjustable with respect to said first member to establish a predetermined operating direction, sm'd operating direction being at a predetermined angle with respect to said horizontal reference direction,

(d) extension means rotatably coupled to the second member of said universal means, said extension means being rotatable in a plane perpendicular to said operating direction,

(f) holding means for supporting a dental tool, and

(g) means coupled to said extension means and to said holding means for translating said holding means in said operating direction.

6. A paralleling device comprising (a) a Wedge-shaped adaptor member,

(12) a swivel block rotatably secured to the end of said adaptor member, the axis of rotation of said swivel block defining a horizontal reference direction,

(0) a universal joint, said universal joint comprising a ball member coupled to said swivel means and having a spherical portion, an externally threaded wrist bearing, and an internally threaded lock nut threadably engaging said wrist bearing, said lock nut maintaining said Wrist bearing in slidable engagement with the spherical portion of said ball member,

(d) holding means for supporting a dental tool, and

(2) means for coupling said holding means to said universal joint, said means permitting translation of said tool holding means in an operating direction determined by the relative positions of the wrist hearing and ball member or" said universal joint and permitting movement of said tool holder in a plane perpendicular to said operating direction, said operating direction being at a predetermined angle with respect to said vertical reference direction.

7. A paralleling device comprising (a) a Wedge-shaped adaptor member,

(b) first and second thermoplastic layers secured to the upper and lower surfaces of said wedge-shaped adaptor member,

(0) a swivel block rotatably secured to the end of said adaptor member, the axis of rotation of said swivel block defining a horizontal reference direction,

(d) a universal joint, said universal joint comprising a ball member coupled to said swivel means and having a serrated spherical portion, an externally threaded Wrist bearing, an internally threaded lock nut threadably engaging said wrist bearing, said lock nut maintaining said wrist bearing in slidable engagement with the spherical portion of said ball member, and an insert radially positioned in said wrist bearing, said insert pressing outward against said lock nut to prevent relative movement of said lock nut and said wrist bearing,

(2) an extension member rotatably coupled to said wrist bearing, the axis of rotation of said extension member being determined by the relative positions of the Wrist bearing and ball member of said universal joint and defining an operating direction, said operating direction being at a predetermined angle with respect to said vertical reference direction,

(f) a slide member coupled to said extension member,

said slide member being translatable in said operating direction and rotatable in a plane perpendicular thereto, and

(g) a holder coupled to said slide member, said holder being adapted for holding a dental tool.

References Cited in the file of this patent UNITED STATES PATENTS 2,318,403 Karlstrom May 4, 1943 2,448,437 Kaplan Aug. 31, 1948 3,063,149 Suga Nov. 13, 1962 FOREIGN PATENTS 836,993 Germany Apr. 17, 1952 

5. A PARALLELING DEVICE COMPRISING (A) A WEDGE-SHAPED ADAPTOR MEMBER, (B) SWIVEL MEANS ROTATABLY SECURED TO THE END OF SAID ADAPTOR MEMBER, THE AXIS OF ROTATION OF SAID SWIVEL MEANS DEFINING A HORIZONTAL REFERENCE DIRECTION, (C) UNIVERSAL MEANS INCLUDING FIRST AND SECOND MEMBERS, SAID FIRST MEMBER BEING ATTACHED TO SAID SWIVEL MEANS AND SAID SECOND MEMBER BEING ANGULARLY ADJUSTABLE WITH RESPECT TO SAID FIRST MEMBER TO ESTABLISH A PREDETERMINED OPERATING DIRECTION, SAID OPERATING DIRECTION BEING AT A PREDETERMINED ANGLE WITH RESPECT TO SAID HORIZONTAL REFERENCE DIRECTION, (D) EXTENSION MEANS ROTATABLY COUPLED TO THE SECOND MEMBER OF SAID UNIVERSAL MEANS, SAID EXTENSION MEANS BEING ROTATABLE IN A PLANE PERPENDICULAR TO SAID OPERATING DIRECTION, (F) HOLDING MEANS FOR SUPPORTING A DENTAL TOOL, AND (G) MEANS COUPLED TO SAID EXTENSION MEANS AND TO SAID HOLDING MEANS FOR TRANSLATING SAID HOLDING MEANS IN SAID OPERATING DIRECTION. 